The present disclosure relates to a disk of a gas turbine and, more particularly, to a structure of a bore part of a gas turbine, in which a groove is formed on the bore part.
In general, a gas turbine is a kind of an internal combustion engine for converting heat energy into mechanical energy while expanding the combustion gas of high temperature and high pressure, produced by an air-fuel mixture after mixing fuel with air compressed under high pressure in a compressor, wherein the compressor and a rotor obtain rotation force from rotor parts.
FIG. 1 shows a related art gas turbine disk and a tie-bolt.
Referring to FIG. 1, in order to form such a compressor rotor part 2 and a turbine rotor part 3, a plurality of compressor rotor disks 21, on which outer circumferential surfaces a plurality of compressor blades 22 are disposed, are connected to each other so as to rotate integrally and, in the same way, a plurality of turbine rotor disks 31, on which outer circumferential surfaces a plurality of turbine blades 32 are disposed, are connected to each other so as to rotate integrally, wherein the compressor rotor disks 21 and the turbine rotor disks 31 are coupled using a tie-bolt 5, which extends penetrating the center parts of the compressor rotor disks 21 and the turbine rotor disks 31.
Herein, the hollow part of the disks 21, which is penetrated by the tie-bolt, is to be a bore part 7, wherein the bore part 7 is applied with maximum stress according to rotational motion. In order to reduce the stress of the bore part 7, a bore radius is reduced. However, there is a limitation on the minimum radius of the bore part 7 because a minimum cooling air path has to be secured. Therefore, there is a problem that the bore part 7 has to be changed in shape at positions, to which maximum stress is applied, so as to reduce the maximum stress while securing a cooling path.